This cross-border conversation had a broad and tragic context. In the early 1830s, following what for most had been nearly two generations of imperfect peace, Comanches, Kiowas, Navajos, and several different tribes of Apaches dramatically increased their attacks upon northern Mexican settlements. While contexts and motivations varied widely, most of the escalating violence reflected Mexico’s declining military and diplomatic capabilities, as well as burgeoning markets for stolen livestock and captives. Indian men raided Mexican ranches, haciendas, and towns, killing or capturing the people they found there, and stealing or destroying animals and other property. When able, Mexicans responded by attacking their enemies with comparable cruelty and avarice. Raids expanded, breeding reprisals and deepening enmities, until the searing violence touched all or parts of nine states.

This is from Brian DeLay, a historian at Cal-Berkeley. Here is a link.